:root {
  --bg: #f8fafc;
  --bg-elevated: #ffffff;
  --fg: #0f172a;
  --fg-muted: #475569;
  --border: #cbd5e1;
  --accent: #1e3a5f;
  --accent-fg: #f0f4f8;
  --danger: #b91c1c;
  --code-bg: #0f172a;
  --code-fg: #e2e8f0;
  --code-radius: 6px;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f172a;
    --bg-elevated: #1e293b;
    --fg: #e2e8f0;
    --fg-muted: #94a3b8;
    --border: rgba(148, 163, 184, 0.35);
    --accent: #1e3a5f;
    --accent-fg: #f0f4f8;
    --code-bg: #020617;
    --code-fg: #cbd5e1;
  }
}

* {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  height: 100%;
  background: var(--bg);
  color: var(--fg);
}

body {
  display: flex;
  flex-direction: column;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

.app-bar {
  display: flex;
  align-items: baseline;
  gap: 16px;
  padding: 14px 24px;
  background: var(--accent);
  color: var(--accent-fg);
}

.app-bar-title {
  font-size: 1.05rem;
  margin: 0;
  font-weight: 600;
}

.app-bar-subtitle {
  font-size: 0.85rem;
  opacity: 0.8;
}

.app-bar-version {
  margin-left: auto;
  font-family: 'SF Mono', Menlo, monospace;
  font-size: 0.8rem;
  opacity: 0.9;
}

.app-main {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 20px;
  padding: 24px;
  min-height: 0;
}

.drop-zone-section {
  flex: 0 0 auto;
}

.drop-zone {
  position: relative;
  border: 2px dashed var(--border);
  border-radius: 12px;
  padding: 28px;
  text-align: center;
  background: var(--bg-elevated);
  cursor: pointer;
  transition: border-color 0.15s ease, background-color 0.15s ease;
}

.drop-zone:hover,
.drop-zone:focus,
.drop-zone.is-drag-over {
  outline: none;
  border-color: var(--accent);
  background: color-mix(in srgb, var(--accent) 5%, var(--bg-elevated));
}

.drop-zone-headline {
  margin: 0 0 6px;
  font-size: 1rem;
  font-weight: 500;
}

.drop-zone-headline code {
  background: rgba(0, 0, 0, 0.08);
  padding: 0 6px;
  border-radius: 4px;
}

@media (prefers-color-scheme: dark) {
  .drop-zone-headline code {
    background: rgba(255, 255, 255, 0.1);
  }
}

.drop-zone-sub {
  margin: 0;
  color: var(--fg-muted);
  font-size: 0.85rem;
}

.drop-zone-status {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
}

/* `display: flex` beats the user-agent `[hidden] { display: none }`. */
.drop-zone-status[hidden] {
  display: none;
}

.spinner {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  border: 3px solid var(--border);
  border-top-color: var(--accent);
  animation: spin 0.9s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.result-section {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 12px;
  min-height: 0;
}

.result-toolbar {
  display: flex;
  gap: 8px;
  align-items: center;
}

.toolbar-divider {
  width: 1px;
  height: 18px;
  background: var(--border);
  margin: 0 4px;
}

.btn {
  font: inherit;
  padding: 6px 12px;
  border-radius: 6px;
  border: 1px solid var(--border);
  background: var(--bg-elevated);
  color: var(--fg);
  cursor: pointer;
}

.btn:hover { background: color-mix(in srgb, var(--accent) 6%, var(--bg-elevated)); }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }

.btn-primary {
  background: var(--accent);
  color: var(--accent-fg);
  border-color: var(--accent);
}
.btn-primary:hover { background: color-mix(in srgb, var(--accent) 85%, black); }
.btn-primary:disabled { background: var(--accent); }

.btn-link {
  border: none;
  background: transparent;
  color: var(--fg-muted);
  text-decoration: underline;
  padding: 6px 4px;
}

.tab-container {
  flex: 1;
  display: flex;
  flex-direction: column;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
  min-height: 0;
}

.tab-bar {
  display: flex;
  gap: 0;
  border-bottom: 1px solid var(--border);
  background: color-mix(in srgb, var(--bg-elevated) 96%, var(--border));
  flex-shrink: 0;
}

.tab {
  appearance: none;
  background: transparent;
  border: none;
  border-right: 1px solid var(--border);
  padding: 10px 16px;
  font-size: 0.85rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--fg-muted);
  cursor: pointer;
  display: flex;
  align-items: baseline;
  gap: 8px;
  transition: background 0.15s ease, color 0.15s ease;
}

.tab:hover {
  background: color-mix(in srgb, var(--accent) 4%, transparent);
  color: var(--fg);
}

.tab.active {
  background: var(--bg-elevated);
  color: var(--fg);
  border-bottom: 2px solid var(--accent);
  margin-bottom: -1px;
}

.tab-meta {
  font-size: 0.7rem;
  font-weight: 400;
  text-transform: none;
  letter-spacing: 0;
  color: var(--fg-muted);
}

.tab-panels {
  flex: 1;
  position: relative;
  min-height: 0;
}

.tab-panel {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  min-height: 0;
}

.tab-panel[hidden] {
  display: none;
}

.cm-host {
  flex: 1;
  min-height: 0;
  overflow: hidden;
}

/* Document tab: outline sidebar + editor side-by-side */
.document-split {
  flex: 1;
  display: grid;
  grid-template-columns: minmax(220px, 280px) 1fr;
  min-height: 0;
  overflow: hidden;
}

.outline-host {
  border-right: 1px solid var(--border);
  background: var(--bg-elevated);
  min-height: 0;
  overflow-y: auto;
  overflow-x: hidden;
}

.outline-host .placeholder {
  padding: 16px 20px;
  color: var(--fg-muted);
  font-style: italic;
}

.cm-host .cm-editor {
  height: 100%;
}

.cm-host .cm-scroller {
  font-family: 'SF Mono', Menlo, monospace;
}

.editor-host {
  background: var(--bg-elevated);
  font-size: 0.95rem;
  min-height: 0;
  overflow-y: auto;
}

.editor-host .placeholder,
.editor-host .stub-message {
  color: var(--fg-muted);
  font-style: italic;
}

.editor-host .stub-message {
  background: color-mix(in srgb, var(--danger) 8%, transparent);
  border: 1px solid color-mix(in srgb, var(--danger) 30%, var(--border));
  border-radius: 6px;
  padding: 12px 14px;
  font-style: normal;
  color: var(--fg);
}

.editor-host .stub-message strong {
  display: block;
  margin-bottom: 4px;
  color: var(--danger);
}

.result-footer {
  display: flex;
  flex-wrap: wrap;
  gap: 16px 24px;
  padding: 10px 14px;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 0.8rem;
  color: var(--fg-muted);
}

.result-footer strong {
  color: var(--fg);
  font-weight: 500;
  margin-right: 4px;
}

.error-banner {
  background: color-mix(in srgb, var(--danger) 8%, transparent);
  border: 1px solid color-mix(in srgb, var(--danger) 30%, var(--border));
  color: var(--fg);
  border-radius: 6px;
  padding: 10px 14px;
  font-size: 0.85rem;
}

/* References tab */
.references-host {
  flex: 1;
  min-height: 0;
  overflow-y: auto;
  background: var(--bg-elevated);
  padding: 16px 20px;
}

.references-host .placeholder {
  color: var(--fg-muted);
  font-style: italic;
}
.reference-diagnostics {
  margin: 16px 0 0 0;
  padding-left: 20px;
  font-style: normal;
  font-size: 0.8rem;
  color: var(--fg);
}
.reference-diagnostics li {
  margin-bottom: 6px;
}
.reference-diagnostics code {
  background: color-mix(in srgb, var(--fg-muted) 14%, transparent);
  padding: 0 4px;
  border-radius: 3px;
  font-size: 0.78rem;
}
.reference-diagnostics .diag-hint {
  display: block;
  margin-top: 2px;
  color: var(--fg-muted);
  font-size: 0.78rem;
}

.reference-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.reference-entry {
  display: grid;
  grid-template-columns: minmax(40px, max-content) 1fr;
  column-gap: 12px;
  row-gap: 2px;
  padding: 10px 0;
  border-bottom: 1px solid var(--border);
  font-size: 0.85rem;
  line-height: 1.4;
}

.reference-entry:last-child {
  border-bottom: none;
}

.reference-label {
  grid-column: 1;
  grid-row: 1 / span 3;
  font-family: 'SF Mono', Menlo, monospace;
  font-size: 0.78rem;
  color: var(--fg-muted);
  align-self: start;
}

.reference-title {
  grid-column: 2;
  font-weight: 500;
  color: var(--fg);
}

.reference-meta {
  grid-column: 2;
  color: var(--fg-muted);
  font-size: 0.8rem;
}

.reference-id {
  grid-column: 2;
  font-size: 0.72rem;
  color: var(--fg-muted);
  background: color-mix(in srgb, var(--fg-muted) 12%, transparent);
  padding: 1px 5px;
  border-radius: 3px;
  width: fit-content;
}

/* Drop section: shrink padding once compact */
.drop-zone-section sciflow-pandoc-drop[compact] {
  display: block;
}

/* Media diagnostics tab */
.media-host {
  flex: 1;
  min-height: 0;
  overflow-y: auto;
  background: var(--bg-elevated);
  padding: 16px 20px;
}
.media-host .placeholder {
  color: var(--fg-muted);
  font-style: italic;
}
.media-summary {
  margin: 0 0 16px;
  font-size: 0.85rem;
  color: var(--fg-muted);
}
.media-summary strong {
  color: var(--fg);
}
.media-grid {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 12px;
}
.media-item {
  display: grid;
  grid-template-columns: 80px 1fr;
  gap: 12px;
  padding: 10px;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--bg);
}
.media-thumb {
  width: 80px;
  height: 80px;
  background: color-mix(in srgb, var(--fg-muted) 8%, transparent);
  border-radius: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  font-size: 0.7rem;
  color: var(--fg-muted);
  text-align: center;
}
.media-thumb img {
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
}
.media-thumb-empty, .media-thumb-error {
  font-style: italic;
}
.media-meta {
  display: flex;
  flex-direction: column;
  gap: 6px;
  min-width: 0;
}
.media-path {
  font-size: 0.75rem;
  word-break: break-all;
  color: var(--fg);
}
.media-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
}
.media-badge {
  font-size: 0.7rem;
  padding: 2px 6px;
  border-radius: 3px;
  font-family: 'SF Mono', Menlo, monospace;
}
.media-badge-ok { background: color-mix(in srgb, #10b981 18%, transparent); color: #047857; }
.media-badge-warn { background: color-mix(in srgb, #f59e0b 22%, transparent); color: #92400e; }
.media-badge-err { background: color-mix(in srgb, var(--danger) 18%, transparent); color: var(--danger); }
.media-badge-info { background: color-mix(in srgb, var(--fg-muted) 14%, transparent); color: var(--fg-muted); }

.media-orphans {
  margin-top: 16px;
  padding: 12px;
  border: 1px solid color-mix(in srgb, var(--danger) 30%, var(--border));
  background: color-mix(in srgb, var(--danger) 6%, transparent);
  border-radius: 6px;
  font-size: 0.8rem;
}
.media-orphans strong {
  color: var(--danger);
}
.media-orphans ul {
  margin: 8px 0 0 0;
  padding-left: 20px;
}
.media-orphans li code {
  font-size: 0.75rem;
  word-break: break-all;
}

/* --- Live mode (File System Access API) --------------------------------- */

.live-mode-action {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-top: 12px;
  flex-wrap: wrap;
}

.live-mode-hint {
  font-size: 0.8rem;
  color: var(--fg-muted);
}

.live-mode-hint-error {
  color: var(--danger);
}

.live-pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.78rem;
  color: var(--fg);
  background: color-mix(in srgb, var(--accent) 12%, transparent);
  border: 1px solid color-mix(in srgb, var(--accent) 30%, var(--border));
  border-radius: 999px;
  padding: 3px 10px;
  max-width: 360px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  transition: opacity 0.15s ease;
}

.live-pill.live-pill-error {
  background: color-mix(in srgb, var(--danger) 10%, transparent);
  border-color: color-mix(in srgb, var(--danger) 35%, var(--border));
  color: var(--danger);
  max-width: 480px;
}